Keefe, author of Snakehead, told The Atlantic Wire on Friday that he'd started reporting his piece in January, using U.S. court documents and trial transcripts to track down three people involved with the Sinaloa cartel, who would speak as sources: A pilot, a drug manufacturer, and a mid-level trafficker. "In a bunch of these cases the people were either doing prison time or had gotten out of prison, so I started tracking people down. A lot of them don’t want to talk. It’s kind of a low-yield form of reporting."

But through it, Keefe has put together a fascinating profile of an organization that rivals in scale the corporate giants of our time: "By most estimates, Sinaloa has achieved a market share of at least 40 percent and perhaps as much as 60 percent, which means that Chapo Guzmán’s organization would appear to enjoy annual revenues of some $3 billion — comparable in terms of earnings to Netflix or, for that matter, to Facebook." And we meet the Sinaloas' infamous leader, Chapo, who sounds like a cross between CEO and Bond villain: "From the remote mountain redoubt where he is believed to be hiding, surrounded at all times by a battery of gunmen, Chapo oversees a logistical network that is as sophisticated, in some ways, as that of Amazon or U.P.S."

Keefe opted not to go to Sinaloa itself, the seat of the cartel's massive operation. He knew he wasn't going to meet Chapo, so what would he achieve? "There was a cost-benefit analysis. Looking at the reporting from people who have gone to Sinaloa, generally what people come back with -- and this is gringo reporters who go up there and ask around -- they come back with color. You can describe Culiacon, the capital there ... And you might get some guy sitting in front of a restaurant saying 'we do not speak of the Choppo.' " But you're not going to get an interview with the man himself. "I decided against that for a number of reasons, primarily that a lot of journalists have been killed in mexico, most of them Mexican journalists." On Thursday, reporter Baez Chino was found dead in Veracruz, the country's 81st journalist killed since 2000.

So Keefe opted for a week in Mexico City, speaking with academics who follow the drug trade, and lots of time leafing through court documents. Eventually, he found a record of a 2006 trial in Arizona, at which Chapo's right-hand man, Miguel Angel Martínez, had testified. He tracked down the court reporter, who sent him a copy of the transcript. Amazingly, it had been untouched by reporters. "People have been writing about Chapo for years and years and they’ve poured over his biography," Keefe said. But here was a document that had never made it into the hands of a journalist or biographer. It included revelations such as Chapo's own use of cocaine, and what Keefe called "trival details," like the fact that he had his own private zoo in Guadalajara that contained tigers and bears. "It was gobsmacking for me to get my hands on this transcript, which has been out in the world and available if you’d found it, since 2006. And to realize nobody had found it."

Thompson, meanwhile, was reporting a much more sensitive story. As she explains in her report, she found out about the Zetas cartel's alleged involvement in U.S. horse racing in December 2011, and in the course of her reporting discovered that the U.S. Department of Justice was also investigating Zetas leader Miguel Ángel Treviño and his ranch-owning brother, José Treviño, which led to arrests this week. "The Times learned of the government’s investigation last month and agreed to hold back this article until Tuesday morning’s arrests," she wrote. But she worked on the story for a lot longer than a month, so how did she keep herself and her sources safe? She hid behind her own reporting, she told PRI's The World:

I was never threatened. I think a lot of the reason for that is that I didn’t make it known that I was looking specifically at Jose Trevino. I did a lot of reporting that made it appear I was looking at something other than him directly. It was complicated and it took us a lot longer to finish this story because of that. But, yes, we thought about safety at every turn and not just for my safety but really for the safety of the people who spoke to me which is why so many people in my story are unidentified. It was mostly for the sake of their safety.

Thanks to the two reports' legwork, we know a lot more about the cartel situation on both sides of the border on Friday than we did on Monday.

This article is from the archive of our partner The Wire.

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